UPDATED 5:05 p.m.

Nolo has officially become a hurricane.

According to the National Weather Service’s 5 p.m. update, Nolo is now a category 1 hurricane and continues to approach the Big Island from the south.

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It is expected to become a major hurricane by Saturday.

UPDATED 3:24 p.m.

Hawaii County will open five additional shelters Friday morning as Tropical Storm Nolo moves closer to Hawaii Island, which is under a tropical storm warning and hurricane watch.

Residents in flood-prone areas are encouraged to consider taking refuge at a shelter or other locations outside of flood risk areas before flooding begins.

Shelters opening Friday at 6 a.m. are:

— Honoka‘a Gym, 45-541 Lehua St., Honoka‘a

— Papa‘aloa Park Annex, 35-1994 Government Main Road, Papa‘aloa

— Pu‘u‘eo Community Center, 145 Wainaku St., Hilo

— Kahilu Town Hall, 67-1182 Lindsey Road, Waimea

— Ocean View Community Center, 92-8924 Leilani Circle, Ocean View

Shelters that opened Wednesday night are:

— Yano Hall, 82-6156 Mamalahoa Highway, Captain Cook

— Naʻalehu Elementary School gym, 95-5545 Mamalahoa Highway, Nāʻālehu

— Robert N. Herkes Gym, 96-1219 Kamani St., Pahala

— Keaʻau Armory, 16-512 Volcano Road, Keaʻau

Shelter occupants are encouraged to bring their own food, water and any necessary medicine. Shelters are pet friendly, but bring your own crate/carrier and leash.

The county is also offering free shuttle service from Naʻalehu to Pahala today for individuals who want to go to the shelter in Pahala. The Mass Transit Agency’s shuttle service is today from 2 p.m.to 6 p.m. from Naʻalehu Elementary School to the shelter at Robert N. Herkes Gym.

“Tropical Storm Nolo continues to strengthen and threaten Hawaii Island,” Mayor Kimo Alameda said in a statement. “We are looking at both the possibility of life-threatening flash flooding and strong, damaging winds, and we encourage everyone to complete their preparations, stay connected to official alerts and weather updates, and secure safe shelter before flooding strikes.”

A tropical storm warning means tropical storm-force winds (39-73 mph) are expected somewhere within this area within the next 36 hours. A hurricane watch is issued when hurricane-force winds (greater than 74 mph) are possible within the next 48 hours.

Nonemergency county services and operations are suspended today and Friday. The closure includes county offices, all park facilities, and regular Hele-On services (fixed routes and paratransit). Solid waste facilities that are scheduled to be open today are open; all solid waste facilities will be closed on Friday and Saturday.

PREVIOUSLY

The National Weather Service today updated its outlook for Tropical Storm Nolo, issuing a tropical storm warning for Hawaii County.

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A tropical storm warning is issued when winds of between 39 mph to 73 mph are expected within the next 36 hours.

As of 11 a.m., Nolo’s maximum sustained winds had increased to 70 mph, up from 60 mph at 5 a.m., according to the Central Pacific Hurricane Center.

The storm remained centered about 285 miles south of South Point and 455 miles south-southeast of Honolulu, but had begun creeping north at 2 mph after sitting nearly stationary overnight.

Tropical-storm-force winds extend outward up to 90 miles from Nolo’s center.

Forecasters said tropical storm conditions are expected to begin on the Big Island by late Friday, with hurricane conditions possible by early Saturday.

The CPHC also raised its rainfall outlook for the Big Island, now forecasting storm-total rainfall of 15 to 30 inches, up from the earlier 15-to-20-inch range, with a maximum of 35 inches still possible in isolated areas.

A National Weather Service statement for the Kona area said the wind threat “has increased from the previous assessment,” urging residents to plan for wind equivalent to a Category 3 hurricane or higher and to urgently complete remaining preparations.

Nolo remains on track to become a hurricane tonight and a major hurricane as it nears the Big Island Saturday, forecasters said.

A flood watch remains in effect through Saturday afternoon for the Big Island.

NWS officials said deep tropical moisture associated with Nolo will bring heavy showers to the Big Island later today and tonight, with the greatest flooding threat on windward and southeast slopes.

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